audio/murmur: update to 1.3.4, fix dependencies after update devel/protobuf to 24.x, take maintainership

After update devel/protobuf to 24.x mumble started link with dosen
libabsl_*.so from devel/abseil.

Changelog: https://github.com/mumble-voip/mumble/releases/tag/1.3.4

Approved by: arrowd (mentor)
MFH: 2024Q1